User:Atrophicshiner/sandbox View history

Turn lanes

The majority of junctions do not need turn lanes at all. Waze gives advanced warning of upcoming turns, it is up to the user to pick the relevant lane for the approaching turn. Turn lanes should only be considered if there is a clear issue usually raised via MPs or URs. A lot of turn lanes are present on the map from the original basemap import and can be removed.

Do not to map turn lanes when...

• the turn lane is too short (less than 200 ft or 60 m)
• the turn lane is not distinct, only separated by a single painted line, from the main direction of travel
• the turn lane splits at or near the main junction stop or give way line.

Turn lane too short

Turn lane not distinct

Splits at or near stop line

Turn lanes may be of benefit

• Only when the turn lane splits from the main carriageway with a clear separation, physical barrier or chevron markings
• Only if an acute angle may lead the user to misunderstand the location of the turn
• Only for better control of u-turns when a junction is too wide to trigger the u-turn prevention mechanism
• Only for complex junctions that benefit from additional instructions.

Clear separation of turn lane

Acute angle of junction

Complex junction

If turn lanes really are of benefit to the driver, then they should be mapped in the following way:

• Do not map the turn lane longer than it is in reality, Waze already has mechanisms for dealing with queuing traffic
• Turn lanes must never cross a side road before a junction, they must start between the side road and main junction to give clear instructions
• The turn lane segments should have no name, so that the instructions read out the name of the next street
• The Road Type should match the type of the roads they lead to (and never ramps). Only the main carriageway stays as the higher Road Type
• The angle at the beginning of the turn lane should be shallow, so that Waze says Keep Left / Right at that point
• The end of the turn lane should have a clear turn instruction near to the give-way point, unless the traffic merges onto the new road with right-of-way.